Author(s) | Joshua D. Marquez, Rhys W. Hughes, James B. Young, Austin M. Evans,* and Brent S. Sumerlin*
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Abstract | Electrochemical methodologies are powerful for the creation and destruction of challenging
chemical functionality. The deployment of these methodologies on macromolecular substrates is
underexplored. We have recently shown that polymers containing N-(acryloxy)phthalimides could be subjected to electrochemical decarboxylation under mild conditions, which led to the formation of transient alkyl radicals. In the presence of an H-atom donor, poly(N-(acryloxy)phthalimide-co-methyl methacrylate) copolymers subjected to these electrolysis conditions produced poly(ethylene-co-methyl acrylate) and poly(propylene-co-methyl acrylate) copolymers, which are difficult to synthesize by direct polymerization. In the absence of an H-atom donor, electrochemical decarboxylation degraded all-methacrylate poly(N(methacryloxy)phthalimide -co-methyl
methacrylate) copolymers with a degradation efficiency of >95% through a β-scission process.
While decarboxylating N-(acyloxy)phthalimides is electrochemically efficient; it leads to significant
mass loss and low atom economies. We have now demonstrated how direct decarboxylation from
poly(acrylic acid) can also yield polyolefins in the presence of an H-atom donor. By using
poly(methyl acrylate-b-acrylic acid), poly(butyl acrylate-b-acrylic acid), and poly(styrene-b-acrylic acid) precursors, block-polyolefins are generated after electrochemical modification, which are challenging to prepare through other methods. Spectroscopic and chromatographic techniques reveal that these transformations are near-quantitative. Electrochemistry is thus shown to be a powerful tool in selective polymer transformations and controlled macromolecular degradation without the need for activated ester handles.
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